Dolly caster



July 19, 1955 c. c. CLIFTON DOLLY CASTER Filed May 8, 1953 Ill-Immlmmllllh INVENTOR. C C//fo/v A 'r TOENEY United States Patent() DGLLY CASTER Chester C. Clifton, Denver, Colo., assigner to The Acorn Company, Denver, Colo., a corporation of Colorado Application May S, 1953, Serial No. 353,735

2 Claims. (Cl. 16-47) This invention is a caster and a method of use of at least two thereof particularly to steerably support and move a large, heavy, and otherwise manually diicultto-manage load, such as safes, lathes, and heavy boxes or crates up and down inclines and around curves.

Other objects ofthe invention will be in part specifically pointed out or will become clear from the following specication wherein reference is made to the accompanying drawing, in which:

Figure 1 is an elevation partly in broken section through a caster mechanism;

Figure 2 is a section taken approximately along a plane as seen from the direction of and along the line indicated by arrows 2 2 in Figure l;

Figure 3 is a view in plan, as seen from above Figures 1 and 2, showing in dotted outlines two relative positions of parts of the caster;

Figure 4 is a plan View of four of the caster assemblies in rolling engagement with a flat floor and in supporting engagement with a load having a bottom plane surface of engagement; and

Figure 5 is an elevational view illustrating the utilization of several of my new casters as a dolly for supporting a rigid cubical body in manually forced transit along way channels toward a truck.

The caster comprises a rectangular steel caster body plate formed with a series of like hinge lugs 12 integral with the plate on one face thereof. The lugs 12 are shown formed with hinge pin holes aligned along a common minor axis of the rectangular plate, oiset from the plate itself and together they constitute a hinge bearing for a hinge pin or bolt 14. The plate 1i) is further formed with a flat top bearing surface 16 preferably parallel to the hinge axis.

The caster further comprises a truck assembly including a series of substantially identical at steel side plates 1S held together in rigidly spaced apart relation on and with a single bolt 2i) threaded therethrough and through like spacing sleeves 22 placed between plate pairs as shown. Plates 18 are held in assembled spaced relation with each other adjacent hinge lugs 12 of the body plate 10 by hinge bolt 14 extending through aligned hinge bearing holes formed through plates 18 for receiving the hinge bolt 14. Bolt 14 is shown arranged on a common vertical plane of symmetry of and perpendicular to the at parallel surfaces of the plates assembled as shown and the plates are all of a shape as shown to form a prominence over which plate 14) may pivot through limited angles from a horizontal position above the trunnions.

Plates 18 are also each formed with pairs of caster wheel shaft bearing holes for receiw'ng two caster wheel bolt axles 24 and 26 therethrough at the base or" an isosceles triangle of which the apex falls at the hinge pin axis, in wheel bearing relation to two sets of several like caster wheels 28 with the wheel axes about equally spaced from the vertical plane of symmetry of bolts 14 and 20.

The truck as so assembled constitutes a support for 2,713,179 Patented July 19, 1955 the body plate 10 for which the hinge axis of pin 14 is always substantially parallel to, and in fixed spaced relation to, a common plane 30 of ioor engagement for the caster.

The body plate 10 is pierced by a pair of steering pin bearing holes 32 on axes perpendicular to the lat top bearing surface 16 thereof and symmetrically onset from hinge axis 14 at the center of plate 10. The caster further comprises a removable rectangular steering plate 33 having parallel top and bottom bearing surfaces with the bottom surface 34 being at to slide on surface 16 bolsterwise. The steering plate has integrally formed therewith a central tubular steering pin 36 t for projecting from surface 34 through either of the steering pin holes. The pin 36 is internally threaded as shown.

With the parts as so described assembled as shown it is evident that plates 1i) and 33 oscillate together about hinge pin 14 and that plate 33 may rotate about the axis of the steering pin hole supported pin 36 as indicated in Figure 3.

Normally at least three such casters support a at bottomed load. In Figure 4, four such casters are shown arranged with their steering pins at one side of their respective hinges for steering purposes. Accordingly, a slight push on the load rightward while the load is in motion as indicated by arrows exerts a steering torque through the steering plates and causes the several truck frames to change the angularities of their shafts 24 and 26 with respect to their steering plates so that the load moves in the new direction thus imparted to the planes of rotation of the wheels 28.

it should be observed that the top surfaces of the steering plates, in engaging a flat bottomed load, are all brought to and held thereby in a common plane parallel to the plane upon which all caster wheels may be rolling. It is evident that the coniiguration of the top surface of the steering plate may be variously made to accommodate objects to which it is to be tted.

Because of the arrangements as above described of each caster within itself, several casters employed beneath a load L as seen in Figure 5 are particularly eifective in moving the load over obstructions and in particularly in transition from one plane of rolling support as 30A to another plane of rolling support 30B intersecting the same and/or to still another such plane as 36C. It will be observed that the entire load L hinges about all hinge axes 14 in all casters simultaneously and that, although the bottom plane of the load changes its angularity to planes 36A and 30B, the steering and hinge plate surfaces remain in their fixed relations to the bottom plane of the load with which they are held in intimate contact by the weight of the load itself. There is, accordingly, a substantially complete absence of binding action in the transition of the load from movements along plane 30A to plane 30B.

Attention is called in particular to the fact that the weight of the entire load is transmitted to pivot bolt 14 and that there is no binding at the pivot between plates 16 and 33 such as that which always occurs with ordinary casters.

What is claimed as new is:

1. A heavy duty steerable dolly caster comprising, a body plate of extended upper surface area, having at least two spaced downwardly projecting lugs having aligned openings for the reception of a hinge bolt, elongated metal side plates having three holes arranged so that lines joining their centers form an isosceles triangle, the hole at the vertex of the triangle receiving the hinge bolt, the holes at the corresponding ends of the base of the triangle forming two pairs one in front and the other to the rear of the hinge bolt, each pair forming supports for an axle bolt, at least one caster wheel rotatably mounted on each axle bolt, the side plates each having a fourth hole positioned substantially midway between the holes at the ends of -the triangle base, a tubular spacer sleeve positioned between the side plates and, a bolt passing through said fourth pair of holes and the corresponding spacer sleeve forming means for holding Ythe side plates in Xed spaced relation, forming a truck having two wheels in tandem, and rockable about the hinge bolt, the body plate having a substantially flat upper surface extending to both sides of the hingebolt to points adjacent vertical planes passing through the axle bolts, and a steering plate of substantially the same size as the body plate resting on the upper surface thereof'with its entire under surface in contact therewith, whereby a load resting on the steering plate will be distributed on both sides of the pivot bolt, the steering plate having a pivot on its under surface and thebody plate having an opening positioned in front of the pivot boltV for the reception of said pivot. Y

V2. A device in accordance with claim l in which the body plate has three downwardly projecting lugs and four side plates two of which are positioned in the spaces between the center lug and the outer lugs and in which the other two side lplates are positioned against the outsides References Cited in the tile of this patent UNITED STATES PATENTS 781,243 Thompson Jan. 3l, 1,658,893 Gladding Feb. 14, 1928 1,847,157 f Wilhelm, S1'.Y lvlar. 1, 1932 2,040,121 Bowen May 12, 1936 2,087,299 Pribil July 20, 1937 2,227,875 Boden Ian. 7, 1941V 2,442,831 Suttles June 8, 1943 2,654,112 Milhizer VOCt. 6, 1953 FOREIGN PATENTS 18,041 Great Britain June 17, 1893 

